not having had sex, or only having a sexual relationship with the person you are married to

In the past, a woman needed to be chaste to make a good marriage. 在过去，只有童贞未破的女子才有可能嫁得好。

They exchanged a few chaste kisses (= not expressing sexual desire). 他们纯洁地互吻了几下。

used to describe decoration or style that is very simple and smooth

I like the simple, chaste lines of their architecture. 我喜欢他们线条简洁朴实的建筑。